An aircraft with a CAS may provide a pilot with information that may enhance the pilot's awareness of situations pertaining to the aircraft (e.g., situational awareness). For example, a CAS display may show a symbol for the pilot's own aircraft, as well as symbols for other aircraft detected within the surveillance volume for the CAS, thereby providing the pilot with situational awareness. A CAS may also provide situational awareness by providing to the pilot traffic advisories (TAs) and resolution advisories (RAs).
An RA is information that may be provided by the CAS to the pilot to recommend a maneuver to increase separation relative to an intruding aircraft. RA information typically consists of a visual indication, changing a displayed symbol for the intruding aircraft, and an aural indication, an announcement played on a CAS speaker recommending a maneuver, such as “climb climb.” Before an RA is provided, the CAS may typically provide a TA, information that does not recommend a maneuver to the pilot, but does indicate that an intruding aircraft has reached a predefined condition representing some collision risk. TA information typically consists of a visual indication, changing a displayed symbol for the intruding aircraft, and an aural indication, an announcement played on the CAS speaker consisting of “traffic traffic.”
A present-day CAS does not distinctly indicate to a pilot in an aircraft that is a member of a formation whether a TA is caused by another formation member aircraft or by a nonmember of the formation. A pilot in a formation member aircraft that receives a TA based on another formation member has the same type of visual and aural indications that would have been received had the TA been based on a nonmember of the formation.
A present-day CAS also provides neither status indications for aircraft engaged in airborne refueling, nor aural indications of the present mode of operation for the CAS.